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000
FXUS61 KAKQ 011218
AFDAKQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WAKEFIELD VA
818 AM EDT FRI AUG 1 2014

.SYNOPSIS...
A FRONTAL BOUNDARY WILL DEVELOP ALONG THE SOUTHEAST COAST TODAY
AS HIGH PRESSURE BECOMES CENTERED WELL OFFSHORE. THE FRONT STAYS
ALONG THE COAST OR JUST INLAND OVER THE MID ATLANTIC REGION...KEEPING
UNSETTLED CONDITIONS IN PLACE THROUGH THE WEEKEND.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LATEST SFC ANALYSIS REVEALS ~1023 MB HI PRES OFF THE MID
ATLANTIC/NE CST AND AN INVERTED TROF OF LO PRES OFF THE CAROLINA
CST. THIS TROF WILL SLIDE TOWARDS THE MID ATLANTIC CST THRU THE
DAY...AND IN ASSOCIATION WITH APPROACHING MID-LEVEL ENERGY AND
INCREASING MOISTURE WILL LEAD TO RAIN LIKELY OVR MUCH OF THE AREA
(EXCEPTION IS THE LWR ERN SHORE WITH 30-50% POPS). DIFFICULT TO
EXACTLY TIME THE PRECIP THRU THE DAY...BUT EXPECT PERIODS OF SHRAS
WITH THUNDER PSBL AS WELL. NO SVR WX ANTICIPATED WITH PARAMETERS
NOT FAVORABLE. MAY TAKE A WHILE FOR PRECIP TO START IN SOME AREAS
WITH STILL DRY LO LEVELS WHICH WILL MOISTEN TOP DOWN. CLOUDS WILL
CONTINUE TO STREAM INTO THE REGION RESULTING IN MOSTLY CLOUDY-
CLOUDY SKIES. TEMPS WILL ONLY MAX OUT IN THE UPR 70S TO MID 80S
WITH THE CLOUDS AND PRECIP IN THE AREA.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/...
UNSETTLED/RATHER WET PATTERN WILL DOMINATE THE FCST AREA TNGT THRU
AT LEAST SUN...AS TROF ALOFT SITS OVR THE OH/TN/MS VALLEYS WHILE A
FRNTL BOUNDARY SETS UP RIGHT ALONG THE CST OR JUST INLAND OVR THE
MID ATLC REGION. THIS SCENARIO WILL RESULT IN A MOIST SFC-ALOFT
FLO OVR THE AREA. THAT COMBINED WITH GOOD CONVERGENCE/LIFT...ESPLY
WHEN WEAK LO PRES AREAS MOVE NNE ALONG THE FRNTL BOUNDARY...WILL
PROVIDE AN IDEAL SETUP FOR PERIODS OF SHOWERS AND POSSIBLY A TSTM
ALL LOCATIONS FM THIS EVENG THRU AT LEAST SUN. SEVERE WX IS NOT
EXPECTED DURING THIS TIME PERIOD...BUT HEAVY RAIN WILL BE
POSSIBLE...ESPLY OVR ERN/SERN CNTIES...TNGT THRU SUN AS PWATS ARE
FCST TO BE BETWEEN 1.75 AND 2.25 INCHES IN THESE AREAS. WILL
HIGHLIGHT IN HWO.

PLENTY OF CLOUDS AND LIKELIHOOD OF PCPN WILL HOLD MAX TEMPS DOWN
OVR THE WEEKEND. HIGHS WILL BE MAINLY IN THE UPR 70S TO LWR
80S...WITH LOWS RANGING FM THE MID 60S TO LWR 70S.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
A STALLED FRONT AND ASSOCIATED PLUME OF ATLANTIC MOISTURE IS
FORECAST TO REMAIN IN VICINITY OF THE ATLANTIC COASTAL PLAIN SUNDAY
NIGHT AND MONDAY. THIS BOUNDARY WILL BE TRAPPED BETWEEN A STRONG
RIDGE OVER THE WESTERN ATLANTIC...AND A TROUGH OVER THE MIDWEST.
THERE ARE SUBTLE MODEL DIFFERENCES AMONGST MEDIUM RANGE
GUIDANCE...WHICH WILL ULTIMATELY AFFECT THE PROBABILITY OF RAIN
DURING THIS TIMEFRAME. 31/12Z GFS REMAINS THE WESTERN-MOST AND HENCE
WETTEST SOLUTION...WHILE THE 31/12Z ECMWF/CMC HAVE THE BOUNDARY
CLOSER TO THE COAST. AT THIS TIME...30-40% POPS (HIGHEST E) WILL BE
MAINTAINED SUNDAY NIGHT AND MONDAY. A COLD FRONT DROPS THROUGH THE
GREAT LAKES MONDAY NIGHT AND TUESDAY...AND THEN INTO THE OHIO VALLEY
BY MIDWEEK. THIS WILL SHOVE THE PLUME OF MOISTURE OFFSHORE...WITH
POPS GRADUALLY DIMINISHING NW-SE THROUGH MIDWEEK. HIGHS SHOULD
AVERAGE IN THE MID 80S MONDAY...AND TREND UPWARD TO THE MID/UPPER
80S TUESDAY...AND UPPER 80S TO AROUND 90 WEDNESDAY/THURSDAY. LOW
TEMPERATURES SHOULD AVERAGE IN THE UPPER 60S TO LOW 70S.

&&

.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
ALTHOUGH COPIOUS AMOUNTS OF MOISTURE NOTED ON RADAR...NOT MUCH
MEASURABLE PCPN HAS FALLEN EAT OF I95 CORRIDOR OVERNIGHT. SHORT
RANGE MODELS CONTINUE TO OVERSPREAD THE PCPN N & E THRU OUT THE
DAY...BUT CONFIDENCE ONLY HIGH ENOUGH TO PUT A TEMPO IN AT RIC
FOR NEXT SVRL HRS. ADDED VCSH TO COASTAL TAF SITES AS ONLY R-
XPCTD THERE.

SCT SHWRS WILL BE PSBL WITH ISLTD LATE AFTRN / EVE TSTRMS
DVLPNG...BUT TIMING THESE RATHER PROBELMATIC ATTM GIVEN THE MODEL
DIFFFERENCES. THUS...KEPT PCPN OUT OF FCST ATTM WITH VFR CIGS XPCTD
DURING THE DAY (CU BTWN 4-5K FT). ADDNTL MOISTURE OVESPRADS THE FA
AFTER 00Z BUT INDICTAED CIGS INTO THE MVFR RANGE FOR THE LAST 6
HOURS OF THE FCST PRD. NAM/GFS INDICATING SOME IFR CIGS WITH RAIN
PSBL LATE IN THE FCST PRD.

OUTLOOK...THREAT FOR SHOWERS/TSTMS CONTINUE INTO THE WEEKEND AS
MOISTURE CONTINUES TO INCREASE ALONG AND AHEAD OF A STALLED
COASTAL BOUNDARY. EXPECT GRADUAL INCREASE IN AREAL COVERAGE OF
SHOWERS SAT/SUN AS MOISTURE RAMPS UP. PERIODIC FLIGHT RESTRICTIONS
WILL BE POSSIBLE IN SHRAS AND TSTMS SAT AFTN AND SUN.

&&

.MARINE...
AN INVERTED TROUGH BECOMES THE DOMINANT FEATURE ALONG THE MID
ATLANTIC COAST TODAY BEFORE SHIFTING INLAND THIS WEEKEND. NO FLAGS
EXPECTED AS BOTH WINDS AND SEAS EXPECTED TO REMAIN BELOW CRITERIA.
THAT BEING SAID...A PERSISTANT SE FLOW RESULTS IN SEAS BUILDING TO
BETWEEN 2-4 FT...HIGHEST 20-40 NM OUT. WINDS BECOME S-SW BY MONDAY
AS ENTIRE SYSTM PUSHES OFFSHORE WITH HIGH PRESSURE BUILDING BACK
INTO THE REGION.

WILL GO WITH A MODERATE RIP CURRENT RISK OVER SOUTHERN BEACHES TODAY
GIVEN A E-SE SWELL AND 2 FT OR SLIGHTLY HIGHER NEARSHORE WAVES. THE
MODERATE THREAT WILL LIKELY WORK ITS WAY NORTH TONIGHT AND SATURDAY.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...MODERATE RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR
     NCZ102.
VA...MODERATE RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR
     VAZ098.
MARINE...NONE.

&&

$$
SYNOPSIS...MAS
NEAR TERM...MAS
SHORT TERM...MAS/TMG
LONG TERM...AJZ
AVIATION...MPR
MARINE...MPR